Method of making skirted nuts



y 1, 1956 J. H. FRIEDMAN METHOD OF MAKING SKIRTED NUTS 3 Sheets-Sheet 1 Filed Jan. 4. 1951 INVENTOR. JOHN H F/P/tDMA/V May 1, 1956 J. H. FRIEDMAN METHOD OF MAKING SKIRTED NUTS 3 Sheets-Sheet 2 INVENTOR. JOl/A/ HFE/[D/i/A/V & Jam

ATTO/P/V'YS Filed Jan. 4, 1951 y 1, 1955 J. H. FRIEDMAN 2,743,466

METHOD OF MAKING SKIRTED NUTS Filed Jan. 4, 1951 3 Sheets-Sheet 5 JNVENTOR. Ej.l5 JOHN H F/P/fDMA/V 27447 Maw;-

United States [ice I 2,743,466 I METHODOF MAKINGSK-IRTED NUTS John H. -Friedman, Titfin, Ohio, assignor to The National Machinery Company, Tiflin, Ohio; :1 corporatian of Ohio Application January 4, 1951, Serial No. 204,4e7

3 Claims. 1 (Cl. 86)

This invention relates to a method and apparatus for making nuts, and more particularly to an improved method and apparatus for making skirted nuts such as are characterized-by having a polygonal body and a circular cross-section skirt' extendingfrom one end face of the body.

The environment of my invention is a machine of the header type in which a die block, carried by the bed frameofthe machine, serves to support a plurality of dies and a reciprocating'header slide is arranged to carry a plurality of tools to effect different operations upon the blanks of stock worked in the dies and wherein a cylindrical blank is cut from valength of rod or wire stock and is worked sequentially in each of the dies to discharge from the last die station va nut completely finished except for the interior threading thereof. Preferably my invention is carried out with a header of this type that is provided with transfer means between the die stations that functions to turn the nut blank end-for-end as it is being transferred from one die station to the next adjacent die station.

It is among the objects of my invention to provide a method and apparatus for making special nuts such as a. castle nut, a cone nut, a stop nut, or similar types of skirted'nuts. By the term skirted nut, as used herein, is meant a nut wherein the main body portion is provided with a polygonal exterior such as the conventional hex and one end face of the body is provided with an integrally formedskirt or shoulder having: a round or circular exterior that-is characterized by a maximum outside diameter which is less than the maximum outside diameter of the polygonal or hex body portion of the nut. The outside diameter of such skirt may vary uniformly outwardly from the body of the nut asin a cone a substantially cylindrical blank is pierced in a pOlYgOnal die so as to simultaneously flow the stock of the blank radially and in the direction of its length to fill the corners of the polygonal die and thereafter upsetting the pierced blank in a polygonal die having a reduced diameter circular cross-section portion so as to moveat least a part of the polygonal pierced blank inwardly to form a skirt having a round or circular exterior'and a polygonal interior resulting from the diameter differential in the pierced 'portionof the polygonal blank, and wherein the web or slug characterized by such polygonal interior configuration is thereafter punched out by a circular cross-sectional punch to provide a hole for threading.

It is a further object of my invention to provide an apparatus for making nuts according to the preceding objects, wherein a polygonal die is closed atone end by a chamfer ring and a piercing tool and a second piercing tool is arranged to be movcdinto the other end of the die so as to simultaneously pierce both ends of a blank within the die, and wherein the second named piercingtool is provided with a shoulder spaced from the end of the toola greater distancethan the chamfer ring 'is spaced from the end of the fi'rstnamcd piercing tool so that the second piercing tool penetrates the blank for a greater extent than the first named piercing tool with the result that arskirt portion is formed around the second named piercing tool characterized by a polygonal exterior and a nut or alternatively the-outside diameter of the skirt may and thereafter upsetting such partially pierced blank in a polygonal die that is provided with a reentrant groove at one endface which merges into the polygonal sidewalls of the die-so as to flow the stock at one end face of the pierced blank radiallyinward.

It is a further object of my invention to provide a method and apparatus for makingnuts according to the precedingv object, wherein the piercing step is characterized by forming a web or slug nearer to one end face of the pierced blank than the other and wherein that portion ofthe blank characterized-by the maximum piercing is utilized to'form the skirt of the finished article.

It is a further object of my inventionto provide a. method and apparatus for making skirted nuts wherein circular interior.

It is 'a further object of my invention to provide an apparatus for making nuts according to the preceding object including a fixed polygonal die having a reentrant circular groove at the end thereof merging with the flat sidewalls of the die in a manner to gather inwardly the skirt portion of the blankinresponse to upsetti'ng'pressure applied to the blank by a tool cooperating with said last named 'die.

Further objects and advantages relating to improved grain structure and How characteristics, long tool life, and work hardened properties of the finished article will appear from the following description and the appendedv drawings wherein:

Fig. 1 is a sectional view of the die apparatus employed to carry out the first step of'the method according to my invention;

Fig. la'is a side elevation of a blank formed by the apparatus shown in Fig. 1;

Fig. 2 is a sectional view of the die and tool apparatus employed. to effect a preliminary upsetting and charmfering operation according to my invention;

Fig. 2a is a side elevation of the blank formed in the apparatus shown in Fig. 2;

Fig. 3 is a sectional view of the die and piercing tool arrangement used to carry out the piercing of the nut blank; 1

Fig.3a is a side elevation of the blank formed in: the

apparatus shown in Fig.3;

Fig. 4 is a sectional view of the die and tool apparatus. employed to effect the upsetting or final. skirt forming.-

operation according-to my invention;

Fig. 4a is a side elevation of the blank formed in the Fig. 5a is-a side elevation of -theblank formedby the" apparatus shown in Fig. 5; Y Fig. 6 is avplan view of the die shown in Fig.1;-

Fig. 6a is a plan view of the blank before insertion in.

the die shown in Fig, 6; I

Fig. 7 is a plan view of the die shown in Fig, 2;, Fig. 7a is 'a' plan'vi'ew' of the the die's'shownin'Fig; 7;

Patented May 1, .1956

blank before. insertion in f Fig. 10 is a plan view of the holding die for the slug punching operation shown in Fig. 5; Fig. a is a plan view of the blank prior to its insertion into the die shown in Fig. 10; Fig. 10b is a plan view of the blank after it has been inserted in the die shown in Fig. 10;

Fig. 11 is a sectional view with parts in elevation of a modified form of web or slug punching apparatus;

Fig. lla is a side elevation of the blank after it has been worked in the apparatus shown in Fig. 11;

Fig. 12 is a sectional view with parts in elevation showing a die apparatus used for making skirted nuts of the cone type according to my invention; Fig. 12a is a side elevation of the blank after it has been worked by the apparatus shown in Fig. 12; and

Fig. 13 is an enlarged view partly in section showing a finished cone nut resulting from the operations illustrated in Figs. 11 and 12.

Referring to the drawings, a die holder 5 is secured in the bed frame of a header type of machine by any suitable means and is arranged in the bed frame in alignment with a tool 6 carried by the header slide of the machine not shown. The die holder 5 carries a die 7 having a circular cross-sectional opening as at 8 and is closed at one end by the knocloout pin 9. It will be understood by those skilled in the art that the knockout 9 is normally urged by the spring 10 to the position shown in Fig. 1 and is limited against further recession at that point so that it may provide an anvil for the cut blank 11 when the header slide tool 6 is moved toward the die 7. It will also be understood that the cut blank 11 may deviate somewhat from a truly flat surface at each end due to the action of the shear which severs such blank 11 from a long length of rod or wire stock. The cut blank 11,.when subjected to the pressure of the opposed tools 6 and 9, is sized and flattened in the die 7 to provide the truly cylindrical blank indicated at 12. This will be referred to herein as the sizing step in my method.

As the header slide carrying the tool 6 recedes from the die 7, the knock-out 9 moves in the usual manner to eject the sized blank 12 into a pair of transfer fingers (not shown) which grip the blank 12, turn it end-for-end and hold it in alignment with the next adjacent die 13. The die 13 is mounted in a die holder 14 in alignment with a header slide tool 15 substantially as described in connection with the die of Fig. l. The inner end of the die 13 is provided with a tool 16 having a depression 17 on the working end thereof with beveled or sloping sidewalls so as to provide a chamfer on the blank worked in die 13 and thus the tool 16 functions both as a chamfering tool and a knock-out. The blank 12, when subjected to the working pressures across the face of the tools 15 and 16, is chamfered, as indicated at 18, in the blank 19. The flat areas of the tools 15 and 16 also effect a preliminary upsetting and consequent flattening against the flat sidewalls of the hex die, as indicated at 20, in the blank 19. This will be referred to herein as the upsetting step in my method.

The transfer fingers turn the upset blank 10 end-forend so as to dispose the blank in alignment with the next adjacent die 21. This rotation of the blank during its transfer disposes the blank, as shown in Fig. 3, with the chamfer 18 uppermost. The die 21 is a hex die corresponding in cross-section to hex die 13 and is held by the die holder 22. The inner end of the die 21, however, is closed by a charnfer ring 23 which surrounds a piercing tool 24. During the Working of the blank in die 21, the piercing tool 24 is maintained in the position shown in Fig. 3 and after the piercing operation is effected the tool 24 moves axially toward the face of the die so as to serve as a knock-out. The piercing tool 24 is pro vided with a taper or bevel 25 that terminates on the periphery of the tool at the inner edge of the chamfer ring 23 in the die so as to form an annular trough around the tool 24. The taper 25 merges into a blunt point as at 26. The header slide tool, carried opposite the die 21, is a piercing tool 27 having a point characterized by a sloping surface 28 and a reentrant curved surface 29. The point 28 of the piercing tool 27 is spaced from the cylindrical body of the tool a greater distance than the point 26 is spaced from the body of the tool 24 and the adjustment of the tool 27, with respect to the die 21, is such that during the piercing operation the tool 27 pierces the blank for a greater axial extent than the piercing tool As the header slide moves forward to pierce the blank 20 in the die 21, the stock of the blank is caused to flow laterally and fill out into the hex corners in the die and at the same time to flow axially around the points of the piercing tools so as to producethe pierced hex blank indicated at 30. This step of my method will be referred to herein as the piercing operation.

The pierced blank 30 is turned end-for-end by the transfer mechanism and is positioned in alignment with the next adjacent die 34. This providees that the face of the blank having the maximum piercing is disposed toward the bottom of the die 34. The die 34 is fixed in a die holder and is closed by a pair of concentric sleeves 36-37 and a knock-out 38. The sleeve 36 is hexagonal on its exterior so as to fit within the hex 39 of the die 34. The interior of the sleeve 36 is circular in cross-section to receive the sleeve 37 which in turn surrounds the end of the knock-out 38. The header slide tool 49, disposed opposite this die station, is provided with a flat annular working face 41 surrounding a flat nosed punch 42. The end of the sleeve 37 surrounding the knock-out is chamfered or beveled, as shown, and along with the circular shoulder on the inner periphery of the outer sleeve 36 forms an annular trough 43. As the header slide advances to work the blank 30 in this die station, a portion of the hex blank is caused to flow inwardly into the annular trough 43 at the bottom of the die. This means that the blank stock theretofore moved outwardly by the tool 27 into a hex form is now caused to fiow inwardly to provide a skirt at one end of the blank. The skirt is indicated as at 44 in the worked blank 45 and is characterized by a circular exterior configuration and hexagonal interior configuration. Referring to the blank 30, it will be noted that at the corners of the hex, for instance as at 31 and 32, the volume of the stock or wall thickness exceeds the wall thickness of the pierced portion intermediate the corners of the blank. This difference in wall thickness when the blank is worked in die 34 produces a hexagonal opening in the blank, wherein the corners of the hex opening are displaced 30 degrees from the corners of the hex body. This characteristic is illustrated in the blank 45, Figs. 9-10. The tool 40, carried by the header slide, provides a fiat washer face 46 on that end of the blank opposite the skirt. This step in my method will be referred to herein as the skirt-forming operation. After the blank 30 is worked in the die station 34, the knock-out 38 is advanced inthe usual manner to eject the formed blank 45 from the die. The nut blank is now fully formed except as to the punching out of the slug or web 47 which is effected in the next die station.

The skirted blank 45 is turned end-for-end and advanced to the slug punching die 50 arranged in a die holder 51. The washer face 46 of the blank 45 is arranged to bear against a sleeve 52 arranged within the hex die 50. .The sleeve 52 supports the nut blank 45 and upon advance of the header slide and punch 53, the slug 47 is punched out and ejected from the slug punching die through the passageway 54 and the punched nut blank 55 thereafter ejected from the machine.

In Figs. 11 and 12, I have shown a modification of the last two stations of the nut forming apparatus, namely, the skirt forming and slug punching station. The apparatus in this modification is particularly suited for the making of cone nuts although it will be understood that the slug punching apparatus of Fig. 11 may be substituted for the slug punching apparatus of Fig. and used in connection with the making of castle nuts or stop nuts. In the making of the cone nuts, as illustrated in Fig. 12, a skirt forming die 60 is fixed in a die holder 61 and the bottom of the die 60 is closed by a pair of concentric sleeves 62, 63, and a knock-out 64. The sleeve 62 is provided with a hex exterior to fit within the hex opening in die 60 and a circular interior to receive the sleeve 63 surrounding the knock-out. The two sleeves 62 and 63 are cut away on their interior and exterior exposed edges, respectively, to jointly provide the cone shaped trough 65 at the bottom of the die 60. The hex blank 66 is preferably formed according to the method and apparatus heretofore described in connection with Figs. 1, 2, and 3, and the blank 66 is worked in the die 60 by a header slide tool 67 constructed and arranged substantially as heretofore described in connection with Fig. 4. In this form, as in the preceding embodiment, the difference in wall thickness between the pierced opening and the flat side of the blank and the pierced opening and the corner of the hex converts the circular pierced opening to a hex opening upon working of the blank in the die 60. The hex opening is displaced angularly 30 degrees from the hex of the nut blank body because the corner thickness of the pierced blank flows inwardly to provide the wall thickness for the skirted blank. The working of the blank in the die 60 produces the cone skirt at 69 in the formed blank 68, wherein the hex interior is indicated at 6911.

The blank 68 is transferred to the slug punching die 70 and the Web or slug 71 is punched therefrom. The slug punching apparatus of Fig. 11 comprises a die holder 72 which is provided with a large diameter axial bore 73 arranged to slidably receive the die ring 74, which in turn supports the die 70. The die ring 74 is backed up by a plurality of spring pressed plungers 75 normally urging the die ring to the upper limit of its travel in the bore 73. A collar 76 is secured to the die holder as at 77 and is provided with a flange overhanging the die ring 74 'so as to limit its upward movement. The end face of the blank opposite the cone or skirt is supported by the fixed sleeve 78. The header slide punch 79 is mounted on the header slide indicated at 81 within a pair of concentric sleeves 82 and 83 movable with respect to each other and with respect to the punch 79. Upon advance of the header slide the end of the punch 79 passes through the opening in the nut blank 68 and thereafter the sleeve 82 advances toward the bed frame and with respect to the punch 79 so as to depress the die 70 against the resistance offered by the springs 75a. This serves to free the nut blank 68 of the die 70 and upon withdrawal of the punch 79, the punched nut 80 is carried therewith so as to free the same of the bed frame die 70. Thereafter the sleeve 83 moves with respect to the punch 79 so as to strip the punched nut 80 off from the end of the punch 79 and thereafter the nut 80 is free to fall by gravity and be discharged from the machine.

Although I have shown and described my invention in considerable detail, it will be appreciated by those skilled in the art that numerous modifications may be made therein without departing from the scope of the appended claims.

WhatIclaim is:

1. A method of making a skirted nut blank having a portion with an exterior surface polygonal in cross-section and a skirt having an exterior surface substantially circular in cross-section, comprising piercing a length of metal stock in a polygonal die to form a pierced blank polygonal in cross-section throughout its length with an axial opening extending into the blank from one end face, engaging said one end face of said pierced blank against an axially extending and inwardly inclined annular die surface engaging the outer edge of said one end face, applying pressure to the opposite end of said blank, moving said blank by such pressure axially along said die surface while maintaining the said axial opening substantially free of obstructions to radially inwardly flow and displacing the metal of the blank adjacent said one end face radially inwardly during uch axial movement to form an extending skirt with an exterior surface substantially circular in cross-section.

2. A method of making a skirted nut blank having a portion with an exterior surface polygonal in cross-section and a skirt having an exterior surface substantially circular in cross-section comprising piercing a length of metal stock in a polygonal die to form a pierced blank polygonal in cross-section throughout its length with an axial opening extending into the blank from one end face, engaging said one end face of said pierced blank against an axially extending and inwardly inclined annular die surface engaging the outer edge of said one end face, applying pressure to the opposite end of said blank, moving said blank by such pressure axially along said die surface while maintaining the said axial opening substantially free of obstructions to radially inwardly flow, displacing the metal of the blank adjacent said one end face radially inwardly during such axial movement to form an extending skirt with an exterior surface substantially circular in cross-section, and thereafter punching an axial hole through said blank.

3. A method of making a skirted nut blank having a nut portion with an exterior surface polygonal in cross section and a projecting skirt portion smaller in external diameter than said nut portion comprising piercing a length of metal stock in a polygonal die to form a pierced blank polygonal in cross-section throughout its length with an axial opening extending into the blank from one end face, engaging said one end face of said pierced blank against an axially extending and inwardly inclined die surface engaging the outer edge of said one end face, applying pressure to the opposite end of said blank, moving said blank by such pressure axially along said die surface while maintaining the said axial opening substantially Ifree of obstructions to radially inwardly flow, displacing the metal of the blank surrounding the opening in said one end face radially inwardly during such axial movement to form an extending skirt smaller in external diameter than said pierced blank at all points about its circumference and thereafter punching an axial hole through said blank.

References Cited in the file of this patent UNITED STATES PATENTS 335,195 Heiser Feb. 2, 1886 1,494,385 Smith May 20, 1924 1,993,137 Gibney Mar. 5, 1935 2,013,460 Erdman Sept. 3, 1935 2,080,850 Frayer May 18, 1937 2,199,007 Oldham Apr. 30, 1940 2,207,391 Wilcox July 9, 1940 2,380,584 De Loe July 31, 1945 2,393,850 Wilcox Jan. 29, 1946 2,436,342 Wilcox Feb. 17, 1948 2,542,864 Friedman Feb. 20, 1951 FOREIGN PATENTS 601,977 Great Britain May 18, 1948 

